What Was President Eisenhower's Role in the Efforts in 1957

What was President Eisenhower's role in the efforts in 1957 to desegregate Central High School in Little Rock, Arkansas?

A) When segregationist mobs attacked black children and began to riot, he sent in federal troops to keep order.
B) He went on national television and told the American people that segregation was wrong.
C) He ordered his attorney general to file a friend of the court brief that supported the school board's efforts to maintain segregation.
D) He congratulated the governor for being willing to "stand in the schoolhouse door" to keep out black children.